The same study found that children who ate the most omega-3-packed fish had fewer allergies and were less likely to develop asthma by age 7. This follows research revealing that children of women who ate more fish during pregnancy also had reduced asthma risk. "The fatty acids in fish like salmon are believed to boost the immune system by reducing inflammation," says Sicherer.
How soon to introduce fish to your kid's diet? Most children can start after they're comfortable with other solids like cereal and veggies, but check with your pediatrician first. He may suggest waiting longer (especially for shellfish) if your infant already has allergic problems or if there's a strong family history of allergies.
Stick to low-mercury fish like salmon and trout; avoid high-mercury types like swordfish, king mackerel, or tilefish. Tuna is safe in limited amounts; keep your child's intake to one ounce of light canned tuna a week for every 12 pounds he weighs (a 36-pound toddler could safely eat half a can a week, for example).
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